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"The subject of this book is the physics of vortices. A detailed analysis of the dynamics of vortices will be presented. The important topics of vorticity and molecular spin will be dealt with, including the electromagnetic analogy and quantization in superfluids. The effect of molecular spin on the dynamics of molecular nano-confined fluids using the extended navier-stokes equations will also be covered, especially important to the theory and applicability of nanofluidics and associated devices. The nanoscale boundary layer and nanoscale vortex core are regions of intense vorticity (molecular spin). It will be shown, based on molecular kinetic theory and thermodynamics, that the macroscopic (solid body) rotation must be accompanied by internal rotation of the molecules. Electric polarization of the internal molecular rotations about the local rotation axis, the Barnett effect, occurs. In such a spin aligned system, major changes in the physical properties of the fluid result. "

"Sebagai upaya dalam memahami netralisasi virus H5N1 oleh antibodi manusia, simulasi dinamika molekuler dua kompleks antibodi-antigen dilakukan. Tiga struktur molekul yang membentuk dua kompleks tersbeut dibentuk termasuk antigen hemagglutinin Vietnam 2IBX, hemagglutinin Indonesia CDC, dan fragmen variabel dari antibodi 8H5 atau 8H5Fv.Dalam penelitian ini komplesks 8H5Fv-2IBX dan 8H5Fv-CDC diproduksi melalui pemodelan struktur molekul, homology modeling, dan molecular docking. Dua kompleks tersebut lalu melewati simulasi dinamika molekuler selama 2 nanosekon untuk menginvestigasi kestabilan struktur kompleks dan aktivitas netralisasi yang dapat diamati dengan berfokus pada epitope netralisasi masing ? masing hemagglutinin yang didapatkan hasil molecular docking.Didapatkan bahwa sifat dinamis atom ? atom pembentuk molekul tidak menihilkan aktivitas netralisasi. Dengan mengamati epitope netralisasi masing ? masing hemagglutinin juga didapatkan bahwa aktivitas netralisasi lebih efektif pada hemagglutinin 2IBX (Vietnam) dibandingkan dengan hemagglutinin Indonesia (CDC) berdasarkan kalkulasi solvent accessible surface (SAS), energi, root mean square displacement (RMSD), dan analisis okupansi ikatan hidrogen.

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In an effort to study the H5N1 virus neutralisation by a human antibody, molecular dynamics simulations on two antibody-antigen complexes were conducted. Three molecular structures were formed in this study including the Vietnamese hemagglutinin 2IBX, the Indonesian hemagglutinin CDC, and a variable fragment of the 8H5 antibody or 8H5Fv.

In this study the complexes 8H5Fv-2IBX and 8H5Fv-CDC, that were produced by molecular modeling, homology modeling and molecular docking, was subjected to a 2 nanosecond molecular dynamics simulation each to investigate the stability of such complexes and the maintenance of the neutralising activity that was observed by focusing on the neutralising epitopes that were predicted by molecular docking.

It is was found that the dynamic nature of the molecules in study did not negate the steric hindrance occuring from the antibody variable fragment 8H5Fv with the hemagglutinins, therefore suggesting that the 8H5 antibody should be able to neutralise these two hemagglutinins. By solvent accessible surface (SAS) calculations, energy analysis, root mean square displacement (RMSD) analysis, and also hydrogen bond occupance it was also found that the the 8H5Fv seem to be more effective against the 2IBX (Vietnamese) hemagglutinin than against the CDC (Indonesian) hemagglutinin."

"Penyakit yang disebabkan oleh infeksi virus dengue telah menjadi salah satu masalah kesehatan yang utama di dunia, terutama Asia, Afrika, dan Amerika. Infeksi ini telah menjadi endemik di lebih dari 100 negara. World Health Organization memperkirakan terjadi 100 juta kasus tiap tahun dan sebanyak 2,5 miliar orang atau 40% dari populasi dunia berisiko terjangkit infeksi virus ini. Oleh karena itu, dibutuhkan suatu pengobatan yang bersifat antiviral yang dapat menghambat aktivitas enzim yang berperan dalam replikasi di dalam tubuh. Akhir-akhir ini peptida telah dikembangkan dalam drug design. Dalam penelitian ini digunakan peptida yang sudah dipasarkan secara komersial. Tujuan penelitian ini adalah untuk penapisan peptida siklis komersial yang dapat digunakan sebagai inhibitor protein NS2B-NS3 DENV melalui metode penambatan molekul dan simulasi dinamika molekul. Inhibisi terhadap enzim NS3 protease dapat menyebabkan terhambatnya aktivitas enzimatiknya sehingga poliprotein yang terbentuk dari translasi RNA menjadi tidak dapat dipotong-potong dan poliprotein tetap berada dalam bentuk satu untai panjang yang utuh. Akibatnya protein protein lain yang vital bagi keberlangsungan replikasi virus dengue tidak dapat terbentuk. Penelitian ini menghasilkan ligan Atrial Natriuretic Factor (3-28) (human) sebagai kandidat obat terbaik. Simulasi dinamika molekul menunjukkan bahwa senyawa ini tetap stabil pada kenaikan suhu tubuh menjadi 312 K.

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A disease caused by dengue virus infection has become one of the major health problems in the world, especially Asia, Africa, and America. This infection has become endemic in more than 100 countries. The World Health Organization estimates that 100 million cases occur each year and as many as 2.5 billion people or 40% of the world population at risk of contracting this virus infection. Therefore, we need an antiviral that can inhibit the activity of enzymes involved in the replication in the body. Lately peptide drug design has been developed. This study uses peptides that has been marketed commercially.

The purpose of this study was to screen the commercial cyclic peptides that can be used as an inhibitor of NS3 protein NS2B DENV-through molecular docking and molecular dynamics simulations. Inhibition of NS3 protease enzyme can lead to inhibition of enzymatic activity so polyprotein formed from the translation of RNA can not be cut into pieces and polyprotein remain in the form of a long strand. Proteins that consequently vital for the sustainability of dengue virus replication can not be formed.

This research resulted Atrial natriuretic factor (3-28) (human) as the best drug candidate. Molecular dynamics simulations indicate that this compound remains stable at body temperature of 312 K."